Many construction and mining machines, such as excavators, wheel loaders, hydraulic mining shovels, cable shovels, bucket wheels, and draglines make use of buckets to dig material out of the earth. The buckets can be subjected to extreme wear from the abrasion and impacts experienced during digging. Other construction and mining machines, such as bulldozers, also include blades or other tools that are used to move material such as soil and rock. These blades and other tools can also be subjected to extreme wear through abrasion and other wear mechanisms.
Buckets and blades and other earth-working tools can be protected against wear by including ground engaging tools (GET). GET is typically fashioned as teeth, edge protectors, and other components which are attached to the bucket or blade in the area where the most damaging abrasion and impacts occur. For example, the cutting edge of a bucket can be protected with edge protectors that wrap around and protect the edge.
Thus, one purpose of the GET is to serve as wear material and absorb wear that would otherwise occur on the bucket, blade, or other tool. The GET can be removed when it has been worn and replaced with new GET at a reasonable cost to continue to protect the bucket. Large buckets for draglines and hydraulic shovels can cost a considerable amount, so protecting them against wear and the need for early replacement is important. It is more economical to wear out and replace the GET than to wear out and replace an entire bucket.
In addition to the purpose of protecting against wear, another purpose of the GET may be to provide more effective digging. A tooth mounted on the edge of a bucket, for example, may allow the bucket to penetrate into the soil or rock and dig more effectively with less effort.
Many systems have been proposed and used for removably attaching the GET to buckets and other tools. These systems typically provide a pin or other fastener which holds the GET onto the bucket or other tool. Many problems or disadvantages exist with these known systems. For example, in some conditions the pins can become stuck inside the GET because of rust or because other material gets in the space surrounding the pins and causes binding or adhesion. As another example of a disadvantage of some known attachment systems, some require a hammer to drive in the pin or other fastener. On large GET systems, the hammer required to drive in the pin may likewise be very large, and swinging such a large hammer in difficult field conditions can be objectionable for the technician.
The pin or other fastener must be very secure and reliable and not permit the GET to fall off of the bucket or other work tool, even when the GET is worn extensively. If the GET falls off of the bucket or blade, it could be fed into a crusher or other processing machine and cause damage. Other problems may also occur if the GET inadvertently falls off the bucket, including extensive wear of the exposed area of the bucket left unprotected when the GET fell off which might occur before the problem is detected and repaired. The prior art GET attaching systems have not always held the GET to the bucket or other work tool with adequate reliability.
In general, the prior art GET attaching systems leave room for improvement. This invention provides improvements.